Mechanism of Action of B12-Coenzyme: We will, in collaboration with Dr. Perry (Chemistry Dept., Rice University) synthesize C-5 chirally labeled B12-coenzymes and determine whether the c-5' position becomes racemized in the enzyme-coenzyme complex. We will carry out EXAFS studies on the enzyme bound coensyme in collaboration with Dr. Shulman (Bell Laboratories). We will also study the interaction of proposed intermediates with the apo-enzyme and investigate the mechanism of binding of B12(r) and 5'-deoxyadenosine to the apo-enzyme. Suicide Inactivators: We are attempting to synthesize 00C-CH2-CH2-CH(CF3)(NH3 plus) as a possible inhibitor of glutamate decarboxylase. Proline Racemase: We are developing methods to synthesize C14-labeled Aziridinyh Carboxyl Compounds, an inactivator of proline race mase, in order to further study the geometry of the active site. Especially to test the hypothesis that the active site is located at the intersection of 2 subunits.